Sometimes, technology adoption is driven by the simple things like cabling and compatibility and that can be the case with the migration from 1Gb Ethernet to 10Gb Ethernet.
Sometimes, technology adoption is driven by the simple things like cabling and compatibility and that can be the case with the migration from 1Gb Ethernet (1GbE) to 10Gb Ethernet (10GbE). Before the advent of widespread 10GBase-T, most 10GbE adapters and switches support optical fiber or direct attach copper (DAC) connectivity via expensive SPFs that are not compatible with twisted pair cabling systems typically used in data centers. The result of this was using a switch to provide backwards compatibility with 1GbE. However, the next wave of 10GbE solutions are leveraging low-cost, backwards compatible 10GBase-T that is changing the cost complexity and cabling issues around the migration to 10GbE in the data center.
Analysts such as Crehan Research predict a greater acceleration of 10GbE adoption with a significant factor being emerging support for the 10GBase-T standard (based on the chart below, which indicates 10GBase-T is expected to grow exponentially). 10GBase-T enables 10GbE connections with unshielded or shielded twisted pair cables over distances up to 100 meters. This article explores how data centers can approach the migration to 10GbE using 10GBase-T adapters that are backward compatible with 1GbE and offer support for converged network environments where local area network (LAN) and storage area network (SAN) traffic move over one cable.
Data center wiring today
Today’s data centers have cables covering thousands of miles with a mix of optical and twisted pair cables—optical for Fibre Channel storage networks and twisted pair for IP networks, primarily 1GbE. Optical fiber provides the high-performance bandwidth required for Fibre Channel and twisted pair is the pervasive, cost-effective solution for Ethernet connections.
The biggest challenges with 10GBase-T have been performance characteristics of the cable and the power required to support 10Gb bandwidth with server adapters and switch ports. Part of the solution is Cat 6 and Cat 6a cabling that has improved insulation which minimizes alien cross-talk. The other part of the solution is reduced power requirements for newer 10GbE controllers that are used for server adapters and switches. Reducing the power consumption for the controller allows more power to be used for the physical connection (PHY) that sends signals over the twisted pair cable.
With these improvements, 10GbE adapter and switch providers are introducing 10GBase-T support that is becoming widely available at low prices. This will drive the accelerated adoption of 10GbE. The next step will be next-generation rack servers that ship using 10GBase-T for the LAN on motherboard (LOM) controller that is integrated into the server. In this phase, 10GBase-T will become the default network connection.
Need for backward compatibility
A high percentage of data centers are currently using 1GbE over twisted pair cable, particularly at the server access layer. Deploying 10GbE with optical fiber or DAC connectivity was an all or nothing proposition. 10GbE switches were required at the server access layer since there was no backward compatibility with 1GbE networks. 10GBase-T solves this problem. Servers with 10GBase-T adapters will auto-negotiate to support 1GbE or 10GbE. That enables you to deploy servers today in a 1GbE environment, and then migrate to 10GbE tomorrow, thereby future-proofing your investment.